Method and apparatus for sawing panels



r 1 mamas [72] Inventor: Elimar Wehner Walderseestrasse 70, Hamburg- Germany [21] Application No.: 681,491 [22] Filed: Nov. 8, 1967 [45] Patented: Aug. 4, 1970 [32] Priority: Nov. 11, 1966 [33] Germany [31] No. W42775 [54] METHOD AND APPARATUS FOR SAWTNG PANELS 7 Claims, 4 Drawing Figs.

[52] U.S.Cl. 143/1,

83/47,83/110,83/269,143/47,143/168 [51] lnt.Cl. 1827115/06 [50] Field ofSearch l43/38,46,

Elm ll :r i

Primary Examiner William S, Lawson Assistant Examiner- James F. Coan Att0rneyBeaman and Beaman ABSTRACT: The invention pertains to the method, and the apparatus for performing the method, of sawing large panels in perpendicularly disposed directions to produce a variegated subdivision thereof, The panels are transported in a given direction during processing and are first sawed into a plurality oflongitudinally extending portions parallel to the direction of movement. The leading edges of the portions, after sawing, then engage separate abutments to restrain the panels against movement in the given direction while mounted on a common conveyor. While the panel portions are stopped, the portions are sawed in a direction transverse to the direction of given movement and thereupon the abutments are released from the portion leading edges and the transversely sawed portions are transported in the given direction at a greater rate of speed than previously imparted thereto Sawing devices for the subdividing of panels, such as of plywood or the like, are known wherein first a longitudinal cut is taken on the panels and the saw is then swung through a 90 rotation to perform a transverse cut. Known devices utilize either single blades, or a plurality of blades to perform this type ofsubdivision.

1t is also known to provide panel sawing apparatus wherein one sawing apparatus is employed to perform the longitudinal cuts, while other sawing apparatus performs the transverse cutting.

Patented Aug. 4, 1970' 3,522,825

N I llllhll 6% BY 61M W Patented Aug. 4, 1970 Sheet U.S. PATENT 3,522,825 METHOD AND APPARATUS FOR SAWllNG PANELS To meet the requirements of the consumers for ready-cut panels, that means mostly the requirements of the furniture in dustry, it is desired to obtain variegated subdivision in which the strips formed at first by longitudinal division and still lying side by side at the same level, which are of equal width or also of different widths, are subdivided into portions of different lengths bymutual displacement in a longitudinal direction, for example, and are then subjected to a transverse cut.

This variegated subdivision may be also obtained by laterally spacing the strips thus formed by longitudinal division from each other, so that the transverse separating cuts may be made at first through one strip and then, after displacement of the transverse saw, through the next strip.

In addition, saws have also become known in which a strip first separated longitudinally is passed along below a plurality of transverse saws by means of a transverse feed table, and is thereby subdivided.

It is likewise possible to obtain a variegated subdivision by selectively lifting and lowering these transverse sawing aggregates during the passage of the individual panel strip.

Saws of the first-mentioned type for variegated subdivision I comprise subdivided depositing tables, for example, for the workpieces to perform the longitudinal displacement of the strips, wherein the longitudinal parting cuts must lie on the parting gaps of the table within relatively close reach thereof, so as to be able toperform the longitudinal displacement.

As the loading of these tables may be effected only in a layon or pushing operation and, correspondingly, the discharging also must be effected by pushing-off or taking-off the partial members, such dividing saws are not well suited for a continuous process.

Subdividing saws, which are working to the principle of laterally spacing the strips apart, have already been designed in practical use with roller or web type transport devices; however, a genuine continuous operation is not possible with these devices either, because at first either all the longitudinal or transverse severing cuts must be performed before the transport to discharge the portions may be effected.

Above all, with large or wide dimensions of the starting panels, difficulties will result for the operating personnel when taking-off the portions, because it will either be necessary to take off and stack many plate portions in a minimum amount of time or, when pushing off the entire cutting pattern or image to a depositing ta'ble arranged behind the saw, the portions in the central zone will not be readily accessible with difficulty.

This latter take-off process also requires extra space for the erection ofthe take-off table.

With none of the known sawing plants and devices, however, has it been possible to performa socalled transverse head separating cut to separate a portion extending the entire width of the panel prior to the performance ofthe longitudinal cuts, with a fully automatic runoff of the operations, and in a continuous process.

Such a head member, however, will occur very often when laying out and calculating economic plans of subdivision, so that there is a demand for the construction of a corresponding machine and the development ofa process to carry out such a cutting program.

The subject matter of the present invention is a subdividing saw in which the performance of a head separating cut, the longitudinal division into strips as well as the transverse division even into variegated images of subdivision are guaranteed to take place in a continuous process and in a fully automatic runoff, and wherein the image of subdivision for each new packet of panels pushed-on is formed in the same manner according to a program which may be selected in advance.

In addition, the sub-portions (with the exception of the laterally pushed-off head member) may be continuously removed at the exit end of the machine. Thus, at this place, the work occurring is almost continuous.

With the aid of a known charging device, and the subdividing saw system proposed here, there results for the first time the possibility of performing a variegated subdivision program with automatic charging and continuous subportion removal thereby still answering the requirement for producing a transverse cut for head portions before the longitudinal divi sion.

The feed of the strips of working material after completion of the longitudinal subdivision may be effected not only by a transport belt disposed therebeneath but, to obtain the same effect, driven smooth transport rollers with close roller pitch may also be used.

With the two methods of transport there is a certain danger that during the processing ofpackets of panels the upper strips ofthe plates may be displaced due to friction at the neighboring strips or also by acceleration and braking forces, respectively, with respect to the lower strips. However, for an exact blank to be cut within close dimensional tolerances, it is a prerequisite that the edges of all the layers within a packet of panels lie exactly flush with respect to each other.

It is therefore desirable that the position of the packets with the edges thereof lying flush with respect to each other both in the longitudinal as well as in the transverse direction is secured during the entire subdividing operation at one packet of panels.

The orientation of the strip portions formed by longitudinal subdivision in a direction transversely of the direction of feed, may be secured, for example, by pushing the strips against an oppositely arranged aligning gauge by means of laterally en gaging pushing rams after they have passed the longitudinal saws. The orientation of the end faces, in accordance with the invention, may be obtained by an advancing and clamping device which becomes effective shortly before each transverse subdividing cut (ie. after having pushed the partial strips formed by longitudinal subdivision against the arresting stops) and thereby establishes the position of the strips of the packet of panels with the transverse edges thereof flush with respect to each other.

In this operation care must be taken that the advancing pressure is terminated before the transverse sawing operation is started.

The advancing movement may be stopped by the interposition ofa slip coupling or by use ofa so-called standstill motor in the drive of the advancing device so that the driving mechanism will not be overloaded even with belated switching off. The first mentioned type of drive, in addition, allows for further onward movement of one advancing device in case an adjacent advancing device should have already reached the clamping condition, while the strip lying beside it is still on its forward run in a direction toward the appropriate arresting stop.

It is also possible to provide all the available advancing devices with individual drives, for example, in the form of standstill motors, in order to obtain the same purpose-Le. the independency of the individual longitudinal clamping operations of the strips from each other.

The accompanying drawing shows a schematic representation of two embodiments of the invention. In the drawing,

lFlGS. 1 and 2 show, respectively, side and plan views of an example of embodiment of a panel subdividing saw designed in accordance with the invention,

lFlGS. 3 and 4 show side and plan views of another embodiment of the invention, eliminating those parts which are similar to those of the embodiment of lFllGS. l and 2.

In accordance with FllGS. l and 2, a stack of panels 2 is disposed on a lifting platform 1, the respective upper layer of said stack adapted to be engaged by the pushing arm 3 of a pushing truck 5 movable on a running track 4.

This layer then forms a panel packet 6. A saw gate 10 is arranged above a table stand 7 with supporting rollers 8 and a table surface 9, said saw gate carrying a saw assembly adapted to be moved by means ofa geared motor ll.

The gate is arranged for displacement on guiding rails 13 in order to be able to adjust the position of the transverse separating cut to the dimension desired for the panel or packet cut, respectively. A pushing ram 15 serves to effect the transverse push-out of the packet portion 14.

The remainder 16 of the packet rests at first on a transport band 17 with supporting stand 18.

The transport belt 17 may be coupled to the advancing motor 20 by means ofa clutchable coupling 19.

With the coupling 19 engaged, the remainder 16 of the packet is advanced to the longitudinal saws 22 and 23 while pressing the contact pressure roller 21. These longitudinal saws 22 and 23 are suspended from a transverse beam 24 and may be laterally displaced to adjust the position of the cut.

A sawing table 25 serves to support the material to be cut in the cutting region.

After having passed the longitudinal saws 22 and 23, the material to be cut is passed onward onto the conveyor belt 28 supported in the carrying stand 27 under the pressure of the contact pressure roller 26.

The conveying belt 28 may likewise be engaged with the advancing motor 20 via an electric clutchable coupling 29. It is therefore possible to drive the conveying belts 17 and 28 either singly or in synchronism with each other making use of both couplings 19 and 29.

After the remainder of the packet 16 has passed beneath the longitudinal saws 22 and 23 with all its length, longitudinal partial strips 30, 31 and 32 are thus present on the conveyor belt 28 and may be passed further into the region of the transverse sawing assembly 33 by the transport belt 28.

The transverse sawing assembly 33 is movably suspended from the transverse stand 34 and may perform its cutting 7 stroke with the aid of the geared motor 35.

During the forward running movement of the longitudinal strips 30, 31, and 32, in the example shown, at first the strip 30 is stopped due to engagement with the pivotal stop 36. As the conveying belt 28, however, continues its run, it conveys also the strips 31 and 32 one after the other as far as the associated abutments 37 and 38, slipping beneath the respectively halted strips. The pivoting stops 36, 37, and further stops 36, 37, 38 of like design are displaceably arranged on the guiding rails 44, 45 and 46 so that the arresting position of the longitudinal strips may be correspondingly predetermined.

If the three abutments 36, 37 and 38 are biased and thus the limit switches fitted in these lowered abutments (not shown in the drawing) have been actuated (limit switches being fitted also in the remaining abutments 36, 37 and 38 which, however, are respectively rendered electrically ineffective in the elevated position) the advancing movement of the conveyor belt 28 will automatically be switched off by means of the coupling 29, and the transverse saw assembly 33 begins its cutting stroke by energizing the geared motor 35.

The cut performed in a straight line thus passes through all three strips 31, 32 and 33 and severs portions 39, 40 and 41 of varying lengths.

Upon completion of the transverse severing cut, the abutments 36, 37 and 38 are lifted by means ofan electric sequential circuit and the driving motor 42 of the runout roller conveyor 43 is switched on; all the rollers thereof are driven by means of the motor 42.

Due to the feeding speed of roller conveyor 43 being increased over that of the transport belt 28, a rapid withdrawal ofthe portions 39,40 and 41 is effected, so that the abutments then lowering in accordance with the programmed selection may fall into the gaps between the subportions and the longitudinal strips 30, 31 and 32 following due to the renewed switching-on ofthe conveyor belt 28.

The portions 39,40 and 41 running out onto the roller conveyor 43 may be manually removed or taken away by a conveying and stacking device not shown.

FIGS. 3 and 4 show another embodiment of a panel subdividing transverse saw designed in accordance with the inclamping device likewise belonging to the invention. The panel strips 48, 49 and 50 are disposed on a driven roller conveyor 47 and are pushed onward by the roller feed up to the abutments 51, 52 and 53. Pushing trucks 57, 58 and 59 are suspended from guiding beams 54, 55 and 56 for longitudinal movement above the panel strips. The movement of these pushing trucks is obtained by means of transport chains 60, 61 and 62 which are driven via a mainshaft 63 and a chain 64 by means of an electric motor 65.

The sprockets 66, 67 and 68 seated on the main drive shaft 63 are provided with slip couplings 69, 70 and 71. Camming pushers 72, 73 and 74 adapted to be hinged upwardly are fitted at the pushing trucks 57, 58 and 59 in such a manner, that the lowered position thereof may be exactly determined by adjusting screws 75, 76 and 77.

Upon advance in the workpiece feeding and clamping direction indicated by the arrow, these pushers lie close against the rear edge of the packet strips 48, 49 and 50 with their pushing surfaces adjusted in a vertical position. upon return movement in an opposite direction the pushers being hinged upwardly may slide over the surface of the following panel packet.

To perform the advancing or clamping step, respectively, the electric motor 65 is switched-on in the corresponding sense of rotation so that the camming pushers 72, 73 and 74 come to lie close against the rear edges of the strips of the panel packets 48, 49 and 50. If the first camming pusher has come to lie close against the associated strip the slip coupling will become effective and the clamping pressure adjustable by the slip coupling is maintained until such time that also the two remaining pushers have advanced so much that they have come to lie close against the associated panel strips. When the clamping pressure is achieved at all three strips, the driving motor 65 will be switched-off, and the transverse sawing step may then be initiated by means ofthe transverse sawing device 78.

The roller conveyor 47 comprises all the rollers disposed to the left of the transverse sawing device 78 in FIG. 3', they are driven by a motor 79 in a manner indicated in the drawing. A roller conveyor 80 comprising all the rollers shown to the right of the transverse sawing device 78 in FIG. 3 serves to discharge the variegated cut individual plates at an increased speed, the rollers being driven by a motor 81.

The arresting stops 36, 37, 38; 36, 37', 38 of the embodiment shown in FIGS. l and 2 are arranged above the withdrawal transport path 43. These stops are lifted and lowered by known means, for example hydraulic or pneumatic devices. The same is true with respect to the arresting stops 51, 52, 53 of the embodiment shown in FIGS. 3 and 4.

The advancing devices 57, 58, 59 of the embodiment shown in FIGS. 3 and 4 may be individually stopped by themselves via corresponding switching contacts after having passed through a distance determined by the position ofthe switching contacts, and the clamped condition is obtained by counterpushing the front abutment plates 51, 52, 53 which then only serve as aligning means.

I claim:

1. The method of sawing panels into individual smaller panel portions wherein the panels are transported in a common direction as processed comprising the steps of, transporting a panel in a given direction, passing said panel through a saw while moving in said given direction to form at least two panel portions moving in said given direction, each of said panel portions including a leading edge and a trailing edge, commonly conveying said panel portions in said given direction, separately engaging said leading edge of each of said panel portions to separately stop movement of said panel portions in said given direction, sawing said panel portions in a direction transverse to said given direction while said portions are stopped, releasing said leading edges of said panel portions, and conveying said transversely sawed portions in said given direction from the position where said panel portions vention with an especially advantageous advancing and were stopped.

2. The method of sawing panels as in Claim ll wherein said panel portions are stopped at different locations when moved in said given direction and including the step of displacing said panel portions relative to each other in said given direction while located on a common conveyor.

3. The method of sawing panels as in Claim ll including the step of conveying said panel portions in said given direction after being transversely sawed at a rate greater than the rate at which said panel portions are brought into position for being transversely sawed.

4. The method of sawing panels as in Claim 1 including the step of engaging said rear edge of said panel portions priorto being transversely sawed by biasing means and biasing said panel portions toward said given direction through the rear edges thereof during the transverse sawing.

5. Apparatus for sawing panels into smaller portions comprising, in combination, conveying means for conveying panels in a given direction, first saw means disposed adjacent said conveying means for sawing panels moving on said conveying means in said given direction to form panel portions each having a leading edge and a rear edge, a separate leading edge abutment disposed adjacent said conveyor means for each of said panel portions,

means supporting said abutments for selective movement into and out of the path of movement with the aligned panel portion leading edge, second saw means disposed adjacent said conveying means for sawing said panel portions transverse to said given direction upon said leading edges thereof engaging their associated abutments and the movement of said panel portions ceasing, and means for moving said abutments out of engagement with the associated panel portion leading edge after said portions are transversely sawed.

6. ln apparatus for sawing panels as in Claim 5, a first power driven conveyor located ahead of said second saw means with respect to said given direction and a second power driven conveyor located behind said second saw means with respect to said given direction, said second conveyor having a faster conveying rate than said first conveyor.

7. ln apparatus for sawing panels as in Claim 5, a panel portion rear edge engaging means disposed adjacent said conveying means for each panel portion and engaging the rear edge thereof while the leading edge of the common panel portion is in engagement with its associated abutment, and power means tending to move said rear edge engaging means in said given direction. 

